Camera module

ABSTRACT

The present invention relates to a camera module, comprising: a lens barrel including a body part, and an extension part extending outwardly from the body part; a front body including a through hole into which the body part is inserted, and a placing part on the top of which the extension part is disposed; and an adhesive disposed between the extension part and the placing part, wherein a concave-convex part may be formed on the placing part. The present invention has an effect of enhancing adhesive force between the lens barrel and the front body, thereby maintaining airtightness of an inner space and improving reliability and stability.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.15/748,072, filed on Jan. 26, 2018, which is the National Phase of PCTInternational Application No. PCT/KR2016/008078, filed on Jul. 25, 2016,which claims priority under 35 U.S.C. 119(a) to Patent Application No.10-2015-0106134, filed in the Republic of Korea on Jul. 27, 2015, all ofwhich are hereby expressly incorporated by reference into the presentapplication.

TECHNICAL FIELD

The teachings in accordance with exemplary and non-limiting embodimentsof this invention relate generally to a camera module, and moreparticularly to a camera module used for a vehicle.

BACKGROUND ART

Concomitant with widely generalized dissemination of various mobileterminals and commercialization of wireless Internet services, demandsby consumers related to mobile terminals are diversified to promptvarious types of peripheral devices or additional equipment to bemounted on mobile terminals. Inter alia, camera modules may be one ofthe representative items photographing an object in a still picture or avideo, storing an image thereof, and editing and transmitting the imageas occasion arises.

Recently, demands have greatly increased on miniaturized camera modulesfor multifarious multimedia fields including note-type personalcomputer, camera phones, PDAs, smart phones and toys, video inputdevices including information terminals for monitoring cameras, andvideo tape recorders and vehicular cameras.

Particularly, as demands have increased on driver convenience and safetyin the automobile industries, new technologies assisting a driver byattaching a camera on a vehicle are variably grafted, and technologiesusing cameras are briskly fused with software technologies.Representatively, camera modules used for front and rear cameras andblack boxes may be examples thereof.

However, because, parts used for vehicles, particularly, camera modulescontain important data directly related to safety of passengers andgrasp/understanding of circumstances of affairs/accidents, the cameramodules require high reliability including sturdy solid coupling andstrict waterproof for characteristics thereof.

DETAILED DESCRIPTION OF THE INVENTION Technical Subject

The present invention is to solve the abovementionedproblems/disadvantages, and it is an object of the present invention toprovide a camera module configured to enhance adhesive force between thelens barrel and the front body, thereby maintaining airtightness of aninner space and improving reliability and stability.

Technical Solution

In one general aspect of the present invention, there is provided acamera module, the camera module comprising:

a lens barrel including a body part, and an extension part extendingoutwardly from the body part;

a front body including a through hole into which the body part isinserted, and a placing part on the top of which the extension part isdisposed; and

an adhesive disposed between the extension part and the placing part,wherein a concave-convex part may be formed on the placing part.

Preferably, but not necessarily, the placing part may include a firstsurface formed outwardly of the concave-convex part in opposition to theextension part about an optical axis, wherein the concave-convex part isformed by being more recessed than the first surface.

Preferably, but not necessarily, the placing part may include a secondsurface arranged at an inner side of the concave-convex part about anoptical axis, and the second surface may be formed in opposition to theextension part by being arranged higher than a bottom end of theconcave-convex part.

Preferably, but not necessarily, the placing part may include a firstsurface formed at outside of the concave-convex part in opposition tothe extension part about an optical axis, and a second surface arrangedat an inner side of the concave-convex part about an optical axis,wherein the first and second surfaces may have a mutually differentheight.

Preferably, but not necessarily, a difference between the height of thefirst surface and the height of the second surface may be greater than40 μm, but less than 160 μm.

Preferably, but not necessarily, a surface roughness (Ra) of theconcave-convex part may be greater than 5 μm, but less than 50 μm.

Preferably, but not necessarily, the adhesive may be initially cured inthe process of an alignment between an optical axis of a lens part andan image sensor mounted on a substrate part, and finally cured while thealignment between the optical axis of the lens part and the image sensoris realized.

Preferably, but not necessarily, the initial curing of the adhesive maybe a UV (Ultraviolet) curing.

Preferably, but not necessarily, the final curing may be a heat curingrealized at 75° C.˜90° C.

Preferably, but not necessarily, the adhesive may be of an acrylicepoxy.

Advantageous Effects

The present invention has an advantageous effect of enhancing adhesiveforce between a lens barrel and a front body, thereby maintainingairtightness of an inner space and improving reliability and stability.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view illustrating a camera module according to anexemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a camera module accordingto an exemplary embodiment of the present invention.

FIG. 3 is an enlarged schematic view of “A” section of FIG. 2.

FIG. 4 is a cross-sectional view illustrating a camera module accordingto an exemplary embodiment of the present invention.

FIG. 5 is an enlarged schematic view of “B” section of FIG. 4.

BEST MODE

Some of the exemplary embodiments of the present invention will bedescribed with the accompanying drawings. Detailed descriptions ofwell-known functions, configurations or constructions are omitted forbrevity and clarity so as not to obscure the description of the presentdisclosure with unnecessary detail. Furthermore, throughout thedescriptions, the same reference numerals will be assigned to the sameelements in the explanations of the figures.

Furthermore, the terms “first,” “second,” “A”, “B”, (a), (b) and thelike, herein do not denote any order, quantity, or importance, butrather are used to distinguish one element from another. In thefollowing description and/or claims, the terms coupled and/or connected,along with their derivatives, may be used. In particular embodiments,connected may be used to indicate that two or more elements are indirect physical and/or electrical contact with each other. “Coupled” maymean that two or more elements are in direct physical and/or electricalcontact. However, coupled may also mean that two or more elements maynot be in direct contact with each other, but yet may still cooperateand/or interact with each other. For example, “coupled”, “joined” and“connected” may mean that two or more elements do not contact each otherbut are indirectly joined together via another element or intermediateelements.

Now, a camera module according to an exemplary embodiment of the presentinvention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic view illustrating a camera module according to anexemplary embodiment of the present invention, FIG. 2 is across-sectional view illustrating a camera module according to anexemplary embodiment of the present invention, and FIG. 3 is an enlargedschematic view of “A” section of FIG. 2.

Referring to FIGS. 1 and 2, the camera module according to an exemplaryembodiment of the present invention may include a lens barrel (100) anda front body (200), wherein the lens barrel (100) and the front body(200) may be adhered by an adhesive (not shown).

The lens barrel (100) may accommodate and fix lenses (not shown) byaligning at least one lens (not shown) along an optical axis. The lensbarrel (100) may include a body part (110) and an extension part (120).The body part (110) may have a shape of wrapping the lens and a portionof the body part (110) may be inserted into a through hole (210) of thefront body (200, described later). The extension part (120) may beprotrusively extended to an outside from the body part (110), and mayface an upper surface of the front body (200, described later).

Referring to FIGS. 1, 2 and 3, the front body (200) may be formed at oneside with a through hole (210), wherein the through hole (210) may beinserted by at least one portion of the lens barrel (100), i.e., thebody part (110), to allow the front body (200) and the lens barrel (100)to be coupled. At this time, the front body (200) and the lens barrel(100) may be coupled by an adhesive or screw-connected, where thecoupling using the adhesive and the coupling by screw-connection may beapplied at the same time. The front body (200) may be adhered in such amanner that a placing part (220) formed at an upper surface faces abottom surface of the extension part (120) of the lens barrel (100) andis adhered by an adhesive (described later).

Referring to FIG. 3, the adhesive may be infused into between theplacing part (220) and the extension part (120) by a user to allow thelens barrel (100) and the front body (200) to be adhered. Furthermore,the placing part (220) may include a first surface (222) and the firstsurface (222) may be formed with an extended roughly-formedconcave-convex (221). Furthermore, the adhesive may be coated on theconcave-convex part to elongate an adhered area with the front body(200), whereby the adhesive force can be further reinforced. However, itis a simple example and the present invention is not limited thereto,and the placing part (220) may not be formed with the first surface(222), and but instead formed only with the concave-convex part (221). Asecond surface (223) may be further formed at an inner side of theconcave-convex part (221) and any shape may be applicable as long as anadhered area is increased by the concave-convex part depending on amanufacturer's intention.

Still furthermore, the concave-convex part (221) may be roughly formedin order to increase an area abutted by the adhesive as a means toreinforce an adhesive force of the adhesive, and may be formed byvarious means including etching or laser processing. At this time, asurface roughness (Ra) of the concave-convex part (221) may be greaterthan 5 μm but less than 50 μm. When the surface roughness (Ra) of theconcave-convex part (221) is formed less than 5 μm, the surfaceroughness may be close to that of a plane surface to thereby reduce theadhesive force due to reduced adhesive area within the concave-convexpart (221). Furthermore, when the surface roughness (Ra) of theconcave-convex part (221) is formed greater than 50 μm, an amount ofadhesive accommodated into the concave-convex part (221) may relativelybe more required, such that when adhesive is coated in a same amount ofadhesive as a predetermined amount, the adhesive may not be abutted tothe extension part (120) to decrease the adhesive force. Meantime, thesurface roughness (Ra) of the placing part (220) may be greater than 5μm but less than 50 μm.

FIG. 4 is a cross-sectional view illustrating a camera module accordingto an exemplary embodiment of the present invention, and FIG. 5 is anenlarged schematic view of “B” section of FIG. 4.

FIGS. 4 and 5 illustrate a state where the concave-convex part (221) isformed to be recessed in the placing part (220). That is, a groove maybe formed at the placing part (220), and the groove may be formed withthe concave-convex part (221). The placing part (220) may be formed witha jaw (no reference numeral) formed by the first surface (222) and thesecond surface (223) of the concave-convex part (221). In other words,the first surface (222) may be extensively formed to an outside of theconcave-convex part (221) about an optical axis, and the jaw may beextensively formed to an inside of the concave-convex part 221) about anoptical axis. The jaw may prevent or reduce overflow of adhesive into aninside of the front body (200). At this time, the first and secondsurfaces (222, 223) may have a mutually different height. For example,the first surface (222) may be formed higher than the second surface(223). For example, the first surface (222) may be formed lower than thesecond surface (223). A difference between the height of the firstsurface and the height of the second surface may be preferably greaterthan 40 μm, but less than 160 μm.

As illustrated in the drawings, the first surface (222) is formed higherthan the second surface (223), the purpose of which is to allow moreadhesive to flow nearer to an optical axis than to a directiondistancing from the optical axis, whereby adhesion between the frontbody (200) and the lens barrel (100) can be further reinforced. When adifference between a height of the first surface (222) and a height ofthe second surface (223) is formed less than 40 μm, inducement ofadhesive to a second surface (223) side cannot be easy due to pressurewhen the extension part (120) and the placing part (220) are adhered,and when a difference between a height of the first surface (222) and aheight of the second surface (223) is formed greater than 160 μm, theadhesive may overflow to the through hole (210) of the front body (200)to make it difficult to adhere because there is no sufficient amount ofadhesive accommodated into the concave-convex part (221).

That is, when a difference between a height of the first surface (222)and a height of the second surface (223) is formed less than 40 μm, theadhesive force may be weakened, and when a difference between a heightof the first surface (222) and a height of the second surface (223) isformed greater than 160 μm, the adhesive force may be weakened, or theadhesive may overflow into an inside of the front body (200).Furthermore, the concave-convex part (221) may be roughly formed on asurface thereof in order to increase an area abutted by the adhesive asa means to reinforce the adhesive force of the adhesive, and may beformed through various means such as etching or a laser processing.

At this time, the surface roughness (Ra) of the concave-convex part(220) may be greater than 5 μm but less than 50 μm. When the surfaceroughness (Ra) of the concave-convex part (221) is formed less than 5μm, the surface roughness may be close to that of a plane surface tothereby reduce the adhesive force due to reduced adhesive area withinthe concave-convex part (221), and when the surface roughness (Ra) ofthe concave-convex part (221) is formed greater than 50 μm, an amount ofadhesive accommodated into the concave-convex part (221) may be reducedto weaken the adhesive force. Meantime, the surface roughness (Ra) ofthe placing part (220) may be greater than 5 μm, but less than 50 μm.

The adhesive may be initially cured in the process of adjustment ofalignment between an optical axis of a lens part (no reference numeral)and an image sensor (310) mounted on a substrate part (300), and a finalcure is implemented while the alignment between the optical axis of thelens part and the image sensor is realized, whereby adhesion between thelens barrel (100) and the front body (200) of the camera module can becompleted. At this time, the initial curing of the adhesive is a UV(Ultraviolet) curing, and the final curing of the adhesive may bepreferably a heat curing realized at 75° C.˜90° C. (more preferably at80° C.˜85° C.). The adhesive may be of an acrylic epoxy.

When the heat curing is realized at more than 90° C., the lens made ofplastic may be damaged. Meantime, although it is explained that theadhesive is of an acrylic epoxy according to the present invention, theadhesive may be used with various means as long as the adhesion betweenthe front body (200) and the lens barrel (100) can be performedaccording to a user's intention, and the curing method may be changeddepending on the use of different adhesives.

Although not illustrated in the drawings, the other side of the frontbody (200) may be provided with a rear body (no reference numeral)whereby an inner space can be provided. The inner space may beaccommodated with elements such as a PCB (Printed Circuit Board, noreference numeral) and an image sensor (310) for implementation ofcamera module according to the present invention in order to convert alight received through the lens part to an electrical signal.

Furthermore, as illustrated in FIGS. 2 to 5, the extension part (120)may be formed with a groove (121) facing the placing part (220). At thistime, the adhesive may be inserted into the groove (121) when theextension part (120) and the placing part (220) are adhered by theadhesive, whereby the adhesive force may be strengthened. However, ashape of the groove (121) may depend on the manufacturer's intention.

The camera module according to an exemplary embodiment of the presentinvention may be assembled in the following fashion.

First, a substrate mounted with an image sensor (310) may beaccommodated into the front body (200). Then, a through hole (210)formed on the front body (200) may be inserted with at least one portionof the body part (110) of the lens barrel (100) contained with a lens,whereby the placing part (220) of the front body (200) and the extensionpart (120) of the lens barrel (100) can face each other.

Next, an adhesive is coated on the placing part (220) of the front body(200). That is, coating of adhesive on the placing part (220) may placethe adhesive between the placing part (220) and the extension part(120). The placing part (220) may be formed with a concave-convex part(221) to enlarge an adhered area between the lens barrel (100) and thefront body (200), whereby the adhesive force can be strengthened. Atthis time, an alignment may be adjusted in order to match an opticalaxis of the lens and an optical axis of the image sensor (310) beforethe adhesive is dried. Furthermore, the adhesive is initially curedusing a UV curing at the same time.

Successively, the camera module according to an exemplary embodiment ofthe present invention is heat cured at a temperature of 75° C.˜90° C. tocouple the front body (200) and the rear body (no reference numeral) tothereby complete the assembly of the camera module according to theexemplary embodiment of the present invention. However, an assemblyorder of the camera module according to the exemplary embodiment of thepresent invention is not limited to the abovementioned assembly order,and may be changed depending on the manufacturer's intent or assemblingcircumstances.

For example, although the above explanation has described that the lensbarrel (120) is inserted into the front body (200) and the placing part(220) is coated with the adhesive, it is also possible to first coat theadhesive on the placing part (220) and then the lens barrel (120) isinserted into the through hole (210) of the front body (200) to adherethe extension part (120) and the placing part (220) by facing eachother. Thus, the assembly order is not limited to any one of the abovementioned methods.

Although the aforesaid explanations are simply exemplary embodiments todescribe the camera module according to the present invention, thepresent invention is not limited thereto, and therefore, it should beunderstood that numerous other modifications and embodiments can bedevised by those skilled in the art that will fall within the spirit andscope of the principles of this disclosure.

The invention claimed is:
 1. A camera module, the camera modulecomprising: a lens barrel comprising a body part, and an extension partextending outwardly from the body part; a body comprising a through holeinto which the body part is inserted, and a placing part facing theextension part; and an adhesive disposed between the extension part andthe placing part, wherein the placing part comprises a base surface anda concave-convex part disposed on the base surface, wherein a lowerportion of the concave-convex part is disposed below the base surface,and wherein at least a portion of the extension part facing theconcave-convex part is formed with a flat surface.
 2. The camera moduleof claim 1, wherein the extension part comprises a groove facing theplacing part.
 3. The camera module of claim 2, wherein the adhesive isprovided in the groove.
 4. The camera module of claim 1, wherein asurface roughness (Ra) of the concave-convex part is greater than 5 μm,but less than 50 μm.
 5. The camera module of claim 1, wherein theadhesive is initially cured in the process of an alignment between anoptical axis of a lens part and an image sensor mounted on a substratepart, and finally cured while the alignment between the optical axis ofthe lens part and the image sensor is realized.
 6. The camera module ofclaim 5, wherein the initial curing of the adhesive is a UV(Ultraviolet) curing.
 7. The camera module of claim 5, wherein the finalcuring is a heat curing realized at 75° C.˜90° C.
 8. The camera moduleof claim 1, wherein the adhesive is of an acrylic epoxy.
 9. The cameramodule of claim 1, wherein the base surface extends perpendicular to alongitudinal axis of the through hole.
 10. The camera module of claim 1,wherein the base surface extends radially outward from theconcave-convex part.
 11. The camera module of claim 1, wherein the basesurface extends radially inward from the concave-convex part.
 12. Thecamera module of claim 1, wherein the base surface comprises: a firstsurface located outwardly of the concave-convex part; and a secondsurface located inwardly of the concave-convex part.
 13. The cameramodule of claim 12, wherein the first surface and the second surface arecoplanar.
 14. The camera module of claim 1, wherein an upper portion ofthe concave-convex part is disposed above the base surface.
 15. Thecamera module of claim 1, wherein at least part of the adhesive isdisposed on the concave-convex part.